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Miller" , Eric Dumazet , Jesper Dangaard Brouer , David Ahern , Mina Almasry References: <20241007221603.1703699-1-dw@davidwei.uk> <20241007221603.1703699-16-dw@davidwei.uk> Content-Language: en-US From: Jens Axboe In-Reply-To: <20241007221603.1703699-16-dw@davidwei.uk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/7/24 4:16 PM, David Wei wrote: > From: Pavel Begunkov > > io_zc_rx_tcp_recvmsg() continues until it fails or there is nothing to > receive. If the other side sends fast enough, we might get stuck in > io_zc_rx_tcp_recvmsg() producing more and more CQEs but not letting the > user to handle them leading to unbound latencies. > > Break out of it based on an arbitrarily chosen limit, the upper layer > will either return to userspace or requeue the request. Probably prudent, and hand wavy limits are just fine as all we really care about is breaking out. Looks fine to me. -- Jens Axboe